KR100367189B1 - Fuel supplying apparatus and method for internal combustion engine - Google Patents

Abstract

In the high pressure fuel pump 47 of the fuel supply device, the amount of movement (cam speed) of the plunger 48b when the cam 22a rotates by a unit angle changes in accordance with the phase of the cam 22a. The fuel feeding amount of the high pressure fuel pump 47 is controlled by changing the closing valve start timing of the electromagnetic spill valve 54, but is greatly influenced by the cam speed at the same closing valve start. Therefore, for example, the closing valve start timing of the electromagnetic spill valve 54 in which the maximum amount of fuel feeding amount required for fuel injection is obtained is within a predetermined cam angle range in which the cam speed change due to the cam phase change is constant. The cam profile of the cam 22a is set. And the change of the closing valve start time of the electromagnetic spill valve 54 for adjusting fuel feed amount is performed within the said predetermined cam angle range.

Description

Fuel supplying apparatus and method for internal combustion engine

The present invention relates to a fuel supply apparatus and method for an internal combustion engine.

Background Art In recent years, in internal combustion engines such as engines for automobiles, a type for injecting and supplying fuel directly into a combustion chamber with the intention of improving fuel consumption rate has been put into practical use. In such an internal combustion engine, since fuel injection from a fuel injection valve is performed in response to the pressure in the combustion chamber which becomes high pressure, it is necessary to make the fuel supplied to the same fuel injection valve high pressure. Therefore, the fuel sent from the fuel tank by the feed pump is pressurized by the high pressure fuel pump, and the fuel after the pressurization is fed to the fuel injection valve. As a fuel supply apparatus provided with such a high pressure fuel pump, the thing of Unexamined-Japanese-Patent No. 10-176618 and 10-176619 is known. Here, the fuel supply apparatuses described in these publications are shown in FIG.

As shown in FIG. 9, the high pressure fuel pump 101 of the fuel supply device includes the plunger 103 reciprocating in the cylinder 102 by the cam 100 rotation, the cylinder 102 and the plunger 103. The pressurization chamber 104 partitioned by is provided. The pressurization chamber 104 has a suction passage 107 communicating with the feed pump 106 for delivering fuel from the fuel tank 105, and a spill passage for returning the fuel from the pressurization chamber 104 to the fuel tank 105. The pressure feed passage 110 for feeding the fuel in the 108 and the pressure chamber 104 toward the fuel injection valve 109 is connected to each other. In addition, the high pressure fuel pump 101 is provided with a spill valve 111 for opening and closing between the suction passage 107, the spill passage 108, and the pressure chamber 104.

Then, when the spill valve 111 is open, when the plunger 103 moves in the direction in which the volume of the pressure chamber 104 increases (downward in the figure), that is, when the high pressure fuel pump 101 is in the intake stroke. Fuel is sucked into the pressure chamber 104 from the suction passage 107. In addition, when the plunger 103 moves in the direction in which the volume of the pressurizing chamber 104 decreases (upper part in the drawing), that is, when the high pressure fuel pump 101 is in the pressure feeding stroke, the spill valve 111 is closed. 107 and the spill passage 108 and the pressurizing chamber 104 are cut off, and the fuel in the pressurizing chamber 104 is pumped toward the fuel injection valve 109 via the pressurizing passage 110.

In such a high pressure fuel pump 101, since the fuel is pumped toward the fuel injection valve 109 only during the closing valve timing of the spill valve 111 in the pressure stroke, the closing valve of the same spill valve 111 is started. By adjusting the timing, by adjusting the closing valve timing of the spill valve 111, the fuel feed amount is adjusted. That is, in the fuel feeding amount, it increases by lengthening the closing valve period of the spill valve 111, and decreases by shortening the same closing valve period. And by this fuel feed amount adjustment, the pressure (continuous pressure) of the fuel conveyed to the fuel injection valve 109 is controlled to the target value determined according to the engine operation state, and the fuel injection valve determined by the soft pressure and fuel injection time. The fuel injection amount from 109 becomes appropriate.

The fuel discharged from the feed pump 106 is pressurized by the high pressure fuel pump 101 as described above, and the fuel after the pressurization is pushed toward the fuel injection valve 109 to supply the fuel directly to the combustion chamber. Also, the fuel injection can be performed accurately.

By the way, the fuel feed amount from the high pressure fuel pump 101 is influenced by the cam speed when the spill valve 111 starts closing, that is, the movement amount of the plunger 103 when the cam 100 rotates by a unit angle. . The cam speed at the time of the closing valve start of the said spill valve 111 does not necessarily change (change with a constant inclination) with a fixed amount with respect to the change of the closing valve start time of the same spill valve 111. As shown in FIG. That is, depending on the cam phase, the change amount (tilt) of the cam speed at the time of starting the same closing valve with respect to the change of the closing valve start timing of the spill valve 111 will fluctuate greatly. In this state, even if the fuel feeding amount is adjusted to change the closing valve start time of the spill valve 111 to control the soft pressure to a target value, it is desirable to adjust the fuel feeding amount appropriately by changing the same closing valve start time. It is difficult, and the same soft pressure fluctuates greatly when the soft pressure is controlled to a target value.

SUMMARY OF THE INVENTION An object of the present invention is to provide a fuel supply apparatus for an internal combustion engine that can appropriately adjust the fuel feed rate in accordance with the change of the closing valve start time of the spill valve to improve controllability of the same fuel feed amount.

1 is a cross-sectional view showing an engine to which the fuel supply device of the first embodiment is applied.

2 is a schematic diagram illustrating a fuel supply device of the same engine.

Fig. 3 is a graph showing the amount of lift of the plunger and the cam speed trend with respect to the phase change of the cam driving the high pressure fuel pump.

4 is a block diagram showing an electrical configuration of the fuel supply device.

FIG. 5 is a graph showing a relationship between fuel injection amount (final fuel injection amount QFin) and engine speed NE and closing valve start timing of an electromagnetic spill valve; FIG.

FIG. 6 is a time chart showing the fuel pressure P transition in the delivery pipe when fuel feeding from the high pressure fuel pump and fuel injection by the fuel injection valve are performed in the first embodiment.

7 is a schematic diagram showing a fuel supply device for an engine in a second embodiment.

FIG. 8 is a time chart showing the transition of the fuel pressure P in the delivery pipe when fuel feeding from the high pressure fuel pump and fuel injection by the fuel injection valve are performed in the second embodiment.

9 is a schematic diagram illustrating a high pressure fuel pump.

* Description of the symbols for the main parts of the drawings *

11: engine 11a: cylinder block

12: piston 14: crankshaft

14a: signal rotor 14b: projection

14c: crank position sensor 15: cylinder head

16: combustion chamber 32: intake passage

33: exhaust passage

According to the first aspect of the present invention, the volume of the pressurizing chamber is changed based on the relative movement between the cylinder and the plunger by cam rotation to suck the fuel into the pressurizing chamber and simultaneously feed the same fuel toward the fuel injection valve of the internal combustion engine. To have a fuel pump. The apparatus further includes a spill valve that opens and closes between the spill passage through which the fuel is discharged from the pressurizing chamber and the same pressurizing chamber, and by controlling the closing valve timing of the spill valve, the fuel from the fuel pump to the fuel injection valve. The amount of feeding is adjusted. The fuel supply apparatus changes the start time of the closing valve of the spill valve to control the closing valve period of the same spill valve, so that the fuel feed amount from the fuel pump required for fuel injection of the fuel injection valve can be obtained. A controller is provided. The fuel supply device has a relative movement amount between the cylinder and the plunger when the cam is rotated by the unit angle when the closing valve start time of the spill valve at the time of obtaining the maximum required fuel feed amount is phase of the cam. It is set to be located within a predetermined cam angle range which changes with a constant slope with respect to the change.

The maximum amount of fuel feed amount required when the relative movement amount (hereinafter referred to as cam speed) between the cylinder and the plunger when the cam rotates by a unit angle is within a predetermined cam angle range that is shifted by a predetermined slope with respect to the cam phase change. According to the same configuration in which the closing valve start time of the spill valve at the time of obtaining the gas is changed, when the closing valve start time of the spill valve is changed to adjust the amount of fuel feed from the fuel pump, The cam speed changes with a certain amount of change. The cam speed at the start of the closing valve of the spill valve affects the fuel pumping amount of the fuel pump, but as described above, the cam speed at the start of the same closing valve with a constant change amount for the change of the closing valve start time of the spill valve. When is changed, the fuel pumping amount adjustment by changing the closing valve start time of the spill valve can be appropriately performed, and the controllability of the same fuel pumping amount can be improved.

In the above aspect, the closing valve period control means terminates the closing valve of the spill valve when the cam is near the top dead center, thereby closing the spill valve at the time of obtaining the maximum value of the required fuel feeding amount. It is possible to set the valve start timing to be the same so as to position the closing valve start timing close to the nearest angle position within the predetermined cam angle range. According to the same configuration, the closing valve start timing change of the spill valve for adjusting the fuel feeding amount can be performed in a wide range from the vicinity of the nearest angle to the top of the top dead center within the predetermined cam angle range. .

Moreover, in the said aspect, a cam profile can be set so that the closing valve start timing of the said spill valve at the time of obtaining the maximum value of the said fuel feed amount required may be in the said predetermined cam angle range. According to the same structure, since the cam profile of the cam in a fuel pump is set so that the closing valve start time of the said spill valve at the time of obtaining the maximum value of the fuel feed amount required will be in the said predetermined cam angle range, When the closing valve start timing of the spill valve is changed to adjust the amount of fuel feeding from the pump, the cam speed at the same closing valve start is changed by a constant change amount for this change. Therefore, the fuel pumping amount adjustment by changing the closing valve start timing of the said spill valve can be performed suitably, and the controllability of the same fuel pumping amount can be improved.

In the above aspect, the number of fuel feeds at a predetermined cam angle may be set so that the closing valve start time of the spill valve when the maximum value of the required fuel feed amount is obtained is within the predetermined cam angle range. have. According to the same configuration, since the number of fuel pressure feeds at a predetermined cam angle is set so that the closing valve start time of the spill valve at the time of obtaining the maximum value of the required fuel pressure feed amount is within the predetermined cam angle range, the fuel When the closing valve start timing of the spill valve is changed to adjust the amount of fuel feeding from the pump, the cam speed at the same closing valve start is changed by a constant change amount for this change. Therefore, the fuel pumping amount adjustment by changing the closing valve start timing of the said spill valve can be performed suitably, and the controllability of the same fuel pumping amount can be improved.

In the above aspect, the inner diameter of the pressurizing chamber may be set so that the closing valve start time of the spill valve when the maximum value of the required fuel feeding amount is obtained is within the predetermined cam angle range. According to the same configuration, since the inner diameter of the pressurizing chamber is set so that the closing valve start time of the spill valve when the maximum value of the required fuel feeding amount is obtained is within the predetermined cam angle range, the fuel feeding from the fuel pump is carried out. When the closing valve start timing of the spill valve is changed to adjust the amount, the cam speed at the same closing valve start is changed by a constant change amount for this change. Therefore, the fuel pumping amount adjustment by changing the closing valve start timing of the said spill valve can be performed suitably, and the controllability of the same fuel pumping amount can be improved.

Hereinafter, a first embodiment in which the present invention is applied to a direct injection gasoline engine for a four-cylinder automobile in series will be described with reference to FIGS. 1 to 6.

As shown in FIG. 1, the engine 11 is provided with four pistons 12 (only one is shown in FIG. 1) for each cylinder provided in the cylinder block 11a so that reciprocation is possible. These pistons 12 are connected to the crankshaft 14 which is an output shaft via the connecting rod 13. The reciprocating movement of the piston 12 is converted to rotation of the crankshaft 14 by the connecting rod 13.

The crankshaft 14 is provided with a signal rotor 14a. On the outer circumferential portion of the signal rotor 14a, a plurality of projections 14b are provided for each equiangular angle centering on the axis of the crankshaft 14. Moreover, the crank position sensor 14c is provided in the side of the signal rotor 14a. Then, the crankshaft 14 rotates, and each projection 14b of the signal rotor 14a sequentially passes through the side of the crank position sensor 14c, so that each projection 14b from the same sensor 14c. The pulse-shaped detection signal corresponding to the passage is output.

Moreover, the cylinder head 15 is provided in the upper end of the cylinder block 11a, and the combustion chamber 16 is provided between the cylinder head 15 and the piston 12. As shown in FIG. The intake passage 32 and the exhaust passage 33 are connected to this combustion chamber 16. The combustion chamber 16 and the intake passage 32 communicate with each other by the opening and closing operation of the intake valve 19, and the combustion chamber 16 and the exhaust passage 33 communicate with the opening and closing operation of the exhaust valve 20. It is blocked.

On the other hand, the intake cam shaft 21 and the exhaust cam shaft 22 for rotatably opening and closing the intake valve 19 and the exhaust valve 20 are supported by the cylinder head 15 so that rotation is possible. These intake and exhaust cam shafts 21 and 22 are connected to the crankshaft 14 via timing belts and gears (both not shown) and the like, and the rotation of the crankshaft 14 is transmitted by the same belt and gears. Will be. And when the intake cam shaft 21 rotates, the intake valve 19 opens and closes, and when the exhaust cam shaft 22 rotates, the exhaust valve 20 opens and closes.

In the cylinder head 15, the cam position sensor 21b which detects the projection 21a provided in the outer peripheral surface of the same shaft 21, and outputs a detection signal is provided in the side of the intake cam shaft 21. As shown in FIG. . Then, when the intake cam shaft 21 rotates, the projection 21a of the same shaft 21 passes through the side of the cam position sensor 21b. In this state, detection signals are output at predetermined intervals from the cam position sensor 21b in correspondence with passage of the projection 21a.

The upstream part of the intake passage 32 is provided with a throttle valve 23 for adjusting the intake air amount of the engine 11. The opening degree of this throttle valve 23 is adjusted by driving control of the throttle motor 24 based on the amount of pedaling of the accelerator pedal 25 detected by the accelerator position sensor 26 (the amount of accelerator pedaling). The intake air amount of the engine 11 is adjusted by adjusting the opening degree of the throttle valve 23. Moreover, the vacuum sensor 36 which detects the pressure in the same channel | path 32 is provided in the part located in the downstream side of the throttle valve 23 in the intake channel | path 32. As shown in FIG. The vacuum sensor 36 then outputs a detection signal corresponding to the detected pressure in the intake passage 32.

The cylinder head 15 also has a fuel injection valve 46 for injecting and supplying fuel into the combustion chamber 16 and an ignition plug 41 for igniting a mixer composed of fuel and air filled in the combustion chamber 16. Is installed. When fuel is injected from the fuel injection valve 40 into the combustion chamber 16, the same fuel is mixed with the air sucked into the combustion chamber 16 through the intake passage 32, and the air and the air in the combustion chamber 16 are mixed with each other. A mixer made of fuel is formed. Moreover, the mixer in the combustion chamber 16 is ignited by the ignition plug 41 and combusts, and the mixed mixer after combustion is sent to the exhaust passage 33 as exhaust.

In this engine 11, the combustion system is switched between "stratum combustion" and "homogeneous combustion" in accordance with the engine operating state. That is, when the operating state of the engine 11 is in a high rotational load region requiring high power, fuel is injected into the combustion chamber 16 during the intake stroke to form a homogeneous mixer in which fuel is evenly mixed with air. The "homogeneous combustion" which can obtain a high output by burning a mixer is performed. In addition, when the operating state of the engine 11 is in a low rotational low load region where too high output is not required, the fuel is injected and supplied to the combustion chamber 16 during the compression stroke, so that the fuel concentration around the spark plug 41 is high. Is carried out, and "stratified-combustion" which can obtain favorable ignition even if the average air-fuel ratio of the whole mixer is made the lean side value significantly larger than the theoretical air-fuel ratio is performed.

In the above-mentioned "stratum combustion", since the opening degree of the throttle valve 23 becomes the value of the open side compared with the case of performing "homogeneous combustion" so that the air-fuel ratio of a mixer may be set to a lean side value rather than a theoretical air-fuel ratio, the engine 11 The pumping loss of) is reduced to improve fuel economy. By switching the combustion system in accordance with the engine operating state in this way, it is possible to achieve both the required engine output and fuel efficiency improvement.

By the way, in the direct injection type | mold engine 11 mentioned above, since the inside of the combustion chamber 16 injects and supplies fuel with high pressure, the pressure of the fuel supplied to the fuel injection valve 40 is made to be high pressure. Here, the detailed structure of the fuel supply apparatus of the engine 11 for supplying the high pressure fuel to the fuel injection valve 40 is demonstrated with reference to FIG.

As shown in FIG. 2, the fuel supply apparatus of the engine 11 pressurizes the feed pump 46 which delivers fuel from the fuel tank 45, and the fuel sent by the feed pump 46, and pressurizes fuel. The high pressure fuel pump 47 which pumps toward the injection valve 40 is provided. The supply pressure of the fuel by the feed pump 46 is, for example, 0.3 MPa in this embodiment.

The high pressure fuel pump 47 is provided with the plunger 48b which reciprocates in the cylinder 48a based on the rotation of the cam 22a provided in the exhaust camshaft 22. The cam 22a has two cam peaks 22b for each equiangular angle around the axis of the exhaust camshaft 22. And when the exhaust cam shaft 22 rotates, the plunger 48b will reciprocate in the cylinder 48a according to those cam peaks 22b.

The exhaust cam shaft 22 rotates one rotation (360 ° rotation) while the crankshaft 14 rotates two (720 ° rotation), and the plunger 48b rotates one rotation of the exhaust cam shaft 22. Two round trips. In addition, while the crankshaft rotates by 720 °, four times fuel injection into the combustion chamber 16 from the fuel injection valve 40 is performed in the engine 11. Therefore, in the engine 11, two fuel injections are performed for one reciprocating movement of the plunger 48b in the high pressure fuel pump 47.

Moreover, the high pressure fuel pump 47 is provided with the pressurization chamber 49 which is divided by the cylinder 48a and the plunger 48b, and whose volume changes based on the reciprocating movement of the plunger 48b. The pressurizing chamber 49 is connected to the feed pump 46 via the low pressure fuel passage 50, and the pressure inside the same passage 50 is constant (0.3 MPa) during the low pressure fuel passage 50. The pressure regulator 51 is provided. The pressure chamber 49 communicates with the delivery pipe 53 via the high pressure fuel passage 52 and the check valve 52a, and the delivery pipe 53 corresponds to each cylinder of the engine 11. One fuel injection valve 40 is connected, respectively.

The delivery pipe 53 is provided with a pressure reduction sensor 55 for detecting fuel pressure (continuous pressure) in the same pipe 53. The delivery pipe 53 communicates with the low pressure fuel passage 50 via the check valve 50a. And if the soft pressure detected by the soft pressure sensor 55 becomes excessively high, the check valve 50a will open, and the fuel in the same pipe 53 will flow out into the low pressure fuel passage 50. In this way, the low pressure fuel passage 50 through which the fuel from the delivery pipe 53 flows is maintained at a constant (0.3 MPa) pressure by the pressure regulator 51. Therefore, it is suppressed that the inside of the delivery pipe 53 becomes excessively high by the check valve 50a and the pressure regulator 51.

Moreover, the high pressure fuel pump 47 is provided with the electromagnetic spill valve 54 which communicates and interrupts the said low pressure fuel passage 50 and the said pressurization chamber 49. This electromagnetic spill valve 54 is provided with the electromagnetic solenoid 54a, and opens and closes by controlling the voltage applied to the same solenoid 54a. That is, in the state where electricity supply to the electromagnetic solenoid 54a is stopped, the electromagnetic spill valve 54 is opened by the pressing force of the coil spring 54b, and the low pressure fuel passage 50 and the pressurization chamber 49 are connected in series. It becomes a state.

In this state, when the plunger 48b moves in the direction in which the pressure chamber 49 increases, that is, when the suction stroke of the high pressure fuel pump 47 is performed, the fuel sent from the feed pump 46 is a low pressure fuel. A suction is carried out in the pressurization chamber 49 via the passage 50. Then, when the plunger 48b moves in the direction in which the volume of the pressure chamber 49 contracts, that is, during the pressure feeding stroke of the high pressure fuel pump 47, the electromagnetic spill valve 54 is energized by the energization of the electromagnetic solenoid 54a. Closes the valve against the pressing force of the coil spring 54b, and when the low pressure fuel passage 50 and the pressurizing chamber 49 are blocked, the fuel in the pressurizing chamber 49 is pumped toward the fuel injection valve 40. do.

In this way, the high pressure fuel pump 47 pressurizes the fuel sent out from the feed pump 46 to 12 MPa, for example. Since the pressurized fuel is pumped to the fuel injection valve 40 via the high pressure fuel passage 52 and the delivery pipe 53, the same combustion chamber 16 is resisted against the pressure in the combustion chamber 16 at high pressure. The fuel can be injected directly into the fuel.

In the high-pressure fuel pump 47, the fuel pumping amount adjustment when the plunger 48b reciprocates once, controls the closing valve start time of the electromagnetic spill valve 54 and the same spill valve 54 during the pumping stroke. ) By adjusting the closing valve period. That is, the fuel pumping amount increases when the closing valve period of the solenoid spill valve 54 is increased and the closing valve period is increased, and when the closing valve period is shortened by delaying the closing valve period of the electromagnetic spill valve 54, the fuel feeding rate is increased. The amount will be reduced. As described above, by adjusting the fuel pumping amount of the high-pressure fuel pump 47, the soft pressure in the delivery pipe 53 is controlled to the target soft pressure determined according to the engine operation state.

Here, the shape of the cam peak 22b will be described with reference to Figs. 3A and 3B. 3A is a graph showing a change in lift amount of the plunger 48b with respect to a phase change of the cam 212a, and FIG. 3B shows a cam speed change with respect to the phase change of the cam 22a, that is, the cam 22a is 1. It is a graph which shows the lift amount change of the plunger 48b when it rotates.

The cans 22b of the cam 22a are formed such that the lift amount of the plunger 48b with respect to the phase change of the cam 22a is shifted as shown in Fig. 3A. In such a cam 22a, in the process (suction stroke) in which the cam 22a changes from the top dead center TDC to the bottom dead center BDC, the lift amount of the plunger 48b gradually decreases, and the same cam 22a In the process (pressure stroke) of changing from the bottom dead center to the top dead center, the lift amount of the plunger 48b gradually increases.

In addition, as shown in FIG. 3B, the cam speed gradually increases in the first half of the suction stroke and gradually decreases in the negative direction in the second half of the suction stroke, and gradually increases in the positive direction in the first stroke of the suction stroke. At the same time, the second half gradually decreases with respect to the positive direction. Therefore, when the cam 22a is located near the top dead center in the pressure stroke, the cam speed becomes smaller with respect to the plus direction as the same cam 22a faces the top dead center.

When the fuel is pumped from the high-pressure fuel pump 47, the electromagnetic spill valve 54 is closed during the pressurizing stroke, and when the cam 22a is positioned at the top dead center, the electromagnetic spill valve 54 is closed. ) Is an open valve. By the opening / closing operation of the electromagnetic spill valve 54, fuel pressure feeding from the high pressure fuel pump 47 toward the fuel injection valve 40 is performed. And the fuel feed amount adjustment in the high pressure fuel pump 47 is performed by changing the closing valve start time of the electromagnetic spill valve 54, and adjusting the closing valve timing.

The fuel feeding amount of the high pressure fuel pump 47 corresponds to the area of the portion shown by the oblique line in FIG. 3B, but the area of the oblique portion changes depending on the closing valve timing of the electromagnetic spill valve 54. That is, when the closing valve start time of the solenoid spill valve 54 becomes early and a closing valve period becomes long, the area of the said diagonal part will become large and the fuel pressure amount of the high pressure fuel pump 47 will increase. Moreover, when the closing valve start time of the solenoid spill valve 54 is delayed and the closing valve time is shortened, the area of the said oblique part will become small and the fuel feeding amount of the high pressure fuel pump 47 will reduce.

Next, an electrical configuration of the fuel supply device will be described with reference to FIG. 4.

This fuel supply apparatus is provided with the electronic control unit (henceforth "ECU") 92 for controlling the operation state of the engine 11, such as fuel injection control and fuel pressure control. The ECU 92 is configured as an arithmetic logic operation circuit including a ROM 98, a CPU 94, a RAM 95, a backup RAM 96, and the like.

Here, the ROM 03 is a memory in which various control programs, maps and the like referred to when executing the various control programs are stored, and the CPU 94 performs arithmetic processing based on various control programs and maps stored in the ROM 93. Run The RAM 95 is a memory for temporarily storing the results of calculations in the CPU 94, data input from each sensor, and the like. The backup RAM 96 stores data to be stored when the engine 11 is stopped. It is a nonvolatile memory that stores. The ROM 93, the CPU 94, the RAM 95, and the backup RAM 96 are connected to each other via the bus 97, and to the external input circuit 98 and the external output circuit 99. It is.

The crank position sensor 14c, the cam position sensor 21b, the accelerator position sensor 26, the vacuum sensor 36, the continuity pressure sensor 55, etc. are connected to the external input circuit 98. FIG. On the other hand, the fuel injection valve 40, the electromagnetic spill valve 54, and the like are connected to the external output circuit 99.

The ECU 92 thus configured calculates the engine speed NE based on the detection signal from the crank position sensor 14c. The accelerator pedal amount ACCP is determined based on the detection signal from the accelerator position sensor 26, and the intake air pressure PM is calculated based on the detection signal from the vacuum sensor 36. In the stratified combustion operation, the basic fuel injection amount Qbse is calculated based on the accelerator pedal amount ACCP and the engine speed NE. In the homogeneous combustion operation, the intake pressure PM and the engine speed NE are calculated. Based on this, the basic fuel injection amount Qbse is calculated.

In the stratified combustion operation, the ECU 92 controls the fuel injection valve 40 to drive the engine 11 in an amount corresponding to the final fuel injection amount Qfin obtained from the basic fuel injection amount Qbse. Spray on the compression stroke. In the homogeneous combustion operation, the ECU 92 controls the fuel injection valve 40 to drive the fuel (a quantity of fuel corresponding to the final fuel injection amount Qfin obtained from the basic fuel injection amount Qbse). Inject in the intake stroke of 11).

Since the amount of fuel injected from the fuel injection valve 40 is determined by the soft pressure P in the delivery pipe 53 and the fuel injection time, the soft pressure P obtained based on the detection signal from the soft pressure sensor 55 is determined. Is preferably maintained at a target annual pressure P0 determined according to the engine operation state. However, since the pressure P in the delivery pipe 53 decreases every time fuel injection is performed, the delivery pipe 53 from the high-pressure fuel pump 47 for every predetermined crank angle (for each predetermined cam angle of the cam 22a). It is necessary to carry out fuel feeding to the tank.

When driving the high pressure fuel pump 47 with the cam 22a having two cans 22b, during 720 ° rotation of the crankshaft 14 in which fuel injection from the fuel injection valve 40 is performed four times, The reciprocating movement of the plunger 48b is performed twice. Therefore, when fuel injection is performed by controlling the electromagnetic spill valve 54 for every one reciprocating movement of the plunger 48b, it is 2 from the fuel injection valve 40 with respect to the fuel injection amount from the high pressure fuel pump 47 once. Ash fuel injection is performed. Here, the transition of the soft pressure P in the delivery pipe 53 in this case will be described with reference to FIG. 6.

As shown in FIG. 6, when the electromagnetic spill valve 54 is started, the fuel is pumped from the high pressure fuel pump 47 so that the soft pressure P changes from a low value to a high value with respect to the target soft pressure P0. After that, when the electromagnetic spill valve 54 is changed, the rising of the pressure P is stopped. This rise stops and the fixed soft pressure P decreases step by step every time fuel injection is performed, and after two fuel injections, the pressure decreases to the vicinity of the value before the fuel feeding is performed.

In this case, it is necessary to discharge the amount of fuel required for two fuel injections in one fuel feed so that the annual pressure P is sufficiently increased so that the soft pressure P is not excessively lowered by the two fuel injections. Then, the closing valve start timing (close valve timing) of the electromagnetic spill valve 54 is adjusted so as to sufficiently increase the soft pressure P.

Next, the control procedure of the electromagnetic spill valve 54 is demonstrated.

The ECU 92 has a duty ratio for controlling the closing valve start timing of the electromagnetic spill valve 54 from the soft pressure P, the target soft pressure P0, the final fuel injection amount QFin, the engine speed NE, and the like. (DT) is calculated. The duty ratio DT is a constant cam angle in the cam 22a, for example, the cam angle θ0 located at the pressure stroke of the high-pressure fuel pump 47, so that the electromagnetic spill valve 54 is a closing valve. The ratio (θ / θ 0) of the cam angle θ is shown. The relationship between these cam angles (theta), (theta) 0 is shown in FIG. 3A.

As is apparent from the same figure, the ECU 92 terminates (opening valve) the closing valve of the electromagnetic spill valve 54 when the cam 22a is located at the top dead center. Therefore, as the duty ratio DT becomes larger, the closing valve start time of the electromagnetic spill valve 54 becomes faster, and the fuel feeding amount from the high-pressure fuel pump 47 to the delivery pipe 53 (parts shown by diagonal lines in FIG. 3B). Area) increases.

The duty ratio DT is calculated by the following equation (1).

DT = DTp + DTi + FF... (One)

DTp: Proportional term

DTi: Integral term

FF: feed forward port

In the formula (1), the proportional term DTp is for bringing the annual pressure P close to the target annual pressure P0, and the integral term DTi is for suppressing the difference in the duty ratio DT due to fuel leakage or the like. will be. These proportional terms DTp and integral terms DTi are respectively calculated by the following formulas (2) and (3).

DTp = K1 (P0-P)... (2)

DTi = DTi + K2 (P0-P)... (3)

K1, K2: Coefficient

In addition, in Formula (1), the feedforward term FF supplies fuel required for a predetermined crank angle to the delivery pipe 53 in advance, so that even in the case of engine transient, the soft pressure P is quickly reached. This is to allow close proximity to (P0). This feed forward term FF is calculated with reference to the map based on the final fuel injection amount QFin and the engine speed NE. The feed forward term FF calculated in this way becomes a larger value as the final fuel injection amount QFin becomes larger, and becomes a larger value as the engine speed NE becomes higher.

The ECU 92 controls the energization start timing of the electromagnetic solenoid 54a, that is, the closing valve start timing of the electromagnetic spill valve 54, based on the duty ratio DT calculated from the above equation (1). Here, FIG. 5 shows the relationship between the closing valve start timing of the electromagnetic spill valve 54 with respect to the final fuel injection amount QFin and the engine speed NE.

The solid line L1 in FIG. 5 is a fuel from the high pressure fuel pump 47 when the closing valve start time of the electromagnetic spill valve 54 is changed on the basis of the condition that the engine speed NE is made constant. It shows the change of the feeding amount (fuel feeding amount in one feeding stroke). In addition, the dashed-dotted line L2 in FIG. 5 shows the one fuel feeding amount required for injecting the fuel of the quantity corresponding to the final fuel injection quantity QFin from the fuel injection valve 40. As shown in FIG.

In addition, the solid line L1 shifts to the left side of the drawing as indicated by the two-dot chain line as the engine speed NE increases, and the one-dot chain line L2 is shown in the figure as the final fuel injection amount QFin increases. Will move upwards. And the closing valve start time of the electromagnetic spill valve 54 controlled based on the said duty ratio DT becomes the time (p point in drawing) which the solid line L1 and the dashed-dotted line L2 cross | intersect. Therefore, the closing valve start timing of the electromagnetic spill valve 54 becomes faster as the final fuel injection amount QFin increases and the engine speed NE increases.

By the way, although the fuel delivery amount of the high pressure fuel pump 47 is adjusted by changing the closing valve start time of the electromagnetic spill valve 54, the high pressure fuel pump 47 at the time of starting the closing valve of this electromagnetic spill valve 54 is carried out. Is greatly affected by the cam speed.

As shown in FIG. 3B, normally, in the feeding stroke of the high-pressure fuel pump 47, in the predetermined cam angle range A before the cam 22a is positioned at the top dead center TDC, The cam speed change with respect to the phase change becomes substantially constant, and the cam speed is shifted to the decrease side with a substantially constant slope with respect to the phase change of the same cam 22a. Therefore, if the closing valve start timing of the solenoid spill valve 54 for fuel injection quantity adjustment is performed so that the same closing valve start timing may not deviate from within the said predetermined cam angle range A, accurate fuel delivery volume adjustment will be easy. It can be done.

That is, when the cam speed change with respect to the phase change of the cam 22a is substantially constant, it is difficult to change the amount of change of fuel feed amount at the time of changing the closing valve start timing of the electromagnetic spill valve 54 according to the cam phase. Lose. Therefore, the closing valve start of the same spill valve 54 is started so that the closing valve start timing of the electromagnetic spill valve 54 does not deviate from within the predetermined cam angle range A in which the cam speed is constant with respect to the change of the cam phase. By changing the timing, it is possible to easily adjust the fuel feed amount precisely in bringing the soft pressure P close to the target soft pressure P0.

However, the closing valve start time of the electromagnetic spill valve 54 is changed to obtain a fuel injection amount necessary for performing fuel injection, and the fuel injection amount is increased so that the fuel injection amount required is changed to an advance side value. It becomes easy to deviate from the predetermined cam angle range A to a true angle side.

That is, when the final fuel injection amount QFin is small at the time of engine low load, the amount of fuel injection required for fuel injection decreases, that is, the dashed-dotted line L2 corresponding to the same amount of fuel injection required in FIG. 5. It moves to the bottom of this figure. Therefore, even if the closing valve start timing of the electromagnetic spill valve 54 is located within the predetermined cam angle range A before the cam 22a is located at the top dead center, the required fuel feeding amount can be obtained.

On the other hand, when the final fuel injection amount QFin is large, such as at high engine loads, the fuel injection amount required for fuel injection increases, that is, the one-dot chain line L2 corresponding to the same fuel injection amount required in FIG. Shift to the top of the figure. Therefore, in order to obtain the required fuel feeding amount, the closing valve start timing of the electromagnetic spill valve 54 must be accelerated, so that the same closing valve starting timing may deviate from the predetermined cam angle range A toward the advance side. .

When the closing valve start time of the electromagnetic spill valve 54 is out of the predetermined cam angle range A in this manner, the cam speed change with respect to the phase change of the cam 22a is not constant. Therefore, the amount of change of the fuel feed amount at the time of changing the closing valve start time of the electromagnetic spill valve 54 becomes easy to change according to a cam phase, and it is accurate in bringing the soft pressure P close to the target soft pressure P0. It is difficult to adjust the fuel feed rate. If this fuel feed rate adjustment is not performed correctly, it becomes inadequate that the same soft pressure P will fluctuate greatly when the soft pressure P approaches the target soft pressure P0.

Therefore, in this embodiment, the cam 22a is formed so that the closing valve start timing of the electromagnetic spill valve 54 when the maximum value of the fuel feed amount required for fuel injection or the like is obtained is within the predetermined cam angle range A. do. That is, the cam profile is set so that the lift amount of the plunger 48b when the cam 22a is located near the top dead center is larger than that of the normal cam. By such a cam profile setting, the closing valve start timing of the electromagnetic spill valve 54 when the maximum value of the required fuel feeding amount is obtained is positioned near the nearest angle position in the predetermined cam angle range A. FIG.

In this case, the closing valve start timing change of the electromagnetic spill valve 54 for adjusting the fuel feeding amount is changed in the entire area of the predetermined cam angle range A, i.e., near the nearest angle position within the same predetermined cam angle range A. FIG. Can be performed in a wide range until the cam 22a is located near the top dead center. And only by changing the closing valve start time of the said electromagnetic spill valve 54 within the said predetermined cam angle range A, it becomes possible to perform the same fuel feed amount adjustment to obtain a required fuel feed amount.

In the change of the closing valve start time of the electromagnetic spill valve 54 in this predetermined cam angle range A, the amount of cam speed changes at the start of the closing valve by the same change becomes substantially constant irrespective of the cam phase. Therefore, it becomes difficult to change the amount of change of the fuel feed amount at the time of changing the closing valve start time of the electromagnetic spill valve 54 according to cam phase. Therefore, by changing the closing valve start timing of the electromagnetic spill valve 54, it is possible to easily adjust the exact amount of fuel feeding, and the same pressure P in bringing the pressure P as close to the target pressure P0. ) Can be suppressed from large fluctuations.

According to this embodiment mentioned above, the effect shown below is acquired.

Predetermined cam angle range in which the closing valve start time of the electromagnetic spill valve 54 at the time of obtaining the maximum fuel injection amount required for fuel injection changes the cam speed to the decrease side with a constant slope with respect to the phase change of the cam 22a. The cam profile of the cam 22a in the high pressure fuel pump 47 was set so that it might be located in (A). By performing cam profile setting in this way, the closing valve start timing change of the electromagnetic spill valve 54 for adjusting fuel feed amount is performed within the said predetermined cam angle range A. As shown in FIG. By changing the closing valve start timing of the electromagnetic spill valve 54, it is possible to easily adjust the fuel feed amount precisely, and the same soft pressure P is obtained when the soft pressure P is brought close to the target soft pressure P0. A large fluctuation can be suppressed.

When the closing valve start time of the electromagnetic spill valve 54 when obtaining the maximum value of the fuel feed amount required for fuel injection is located near the most angle position within the predetermined cam angle range A, the electromagnetic spill valve ( The closing valve of 54 ends when the cam 22a is located near the top dead center. Therefore, the closing valve start timing change of the electromagnetic spill valve 54 for adjusting the fuel feeding amount is changed from the vicinity of the nearest angle in the predetermined cam angle range A until the cam 22a is located near the top dead center. It can be performed in a wide range, and the adjustment width of fuel feed amount can be made wide.

Next, a second embodiment of the present invention will be described with reference to FIGS. 7 and 8. In this embodiment, the cam in the high-pressure fuel pump 47 is positioned so that the closing valve start time of the electromagnetic spill valve 54 at which the maximum required amount of fuel feed amount is obtained is located within the predetermined cam angle range A. Instead of setting the cam profile of 22a), the number of fuel pressure feeds from the high-pressure fuel pump 47 at a predetermined cam angle 360 ° is positioned so that the closing valve start timing is within the predetermined cam angle range A. Set it. Thus, in this embodiment, only the method of positioning the closing valve start time of the electromagnetic spill valve 54 in which the maximum required amount of fuel feeding amount is required within the predetermined cam angle range A is different from the first embodiment. Therefore, only the parts different from the first embodiment will be described in this embodiment, and detailed descriptions of the same parts as the first embodiment will be omitted.

In the fuel supply device of the present embodiment shown in FIG. 7, the cam 22a for driving the high pressure fuel pump 47 has four cam peaks 22b for each equiangular angle about the axis of the exhaust cam shaft 22. Have In the high-pressure fuel pump 47 driven by such a cam 22a, the plunger 48b during 720 ° rotation (360 ° rotation of the exhaust cam shaft 22) of the crankshaft 14 where four fuel injections are performed. ) Reciprocates four times. Therefore, one fuel injection is performed for one reciprocating movement of the plunger 48b.

The number of fuel pressure feeds of the high pressure fuel pump 47 during the 360 ° rotation of the cam 22a can be adjusted by controlling the electromagnetic spill valve 54. That is, the fuel feeding from the high pressure fuel pump 47 can be stopped by keeping the electromagnetic spill valve 54 in the open valve state without closing the valve during the feeding stroke of the same pump 47. While the cam 22a is rotated 360 degrees, the reciprocating movement of the plunger 48b is also performed four times, and the crankshaft 14 is rotated 720 degrees, so that fuel injection from the fuel injection valve 40 is performed four times. . The fuel of the high-pressure fuel pump 47 during the 360 ° rotation of the cam 22a is prevented from performing the closing valve of the electromagnetic spill valve 54 during several reciprocating movements of the plunger 48b. The number of times of feeding can be adjusted.

For example, if the closing valve of the electromagnetic spill valve 54 is filtered every single stroke during the reciprocating movement of the four plungers 48b, the number of times of fuel feeding during the 360 ° rotation of the cam 22a is increased. In this case, two fuel injections are performed per one fuel feed. In addition, if the closing valve of the electromagnetic spill valve 54 is performed in all the feeding strokes during the reciprocating movement of the plunger 48b four times, the number of times of fuel feeding pressure during the 360 ° rotation of the cam 22a becomes four times. The fuel injection is performed once per fuel feeding. In this case, since only one fuel injection fuel is sent to the delivery pipe 53 in one fuel injection, the number of times of fuel pressure feeding during the 360 ° rotation of the cam 22a is two times. The amount of feeding can be made about half.

Here, the relationship between the change in the number of times of fuel pressure feed during the 360 ° rotation of the cam 22a and the change in the soft pressure P will be described with reference to FIGS. 8A and 8B. 8A is a time chart showing the transition of the soft-pressure P when the number of times of fuel feeding is made two times during the 360 ° rotation of the cam 22a, and FIG. 8B is the 360 ° rotation of the cam 22a during the rotation. This is a time chart showing the transition of the soft-pressure P when the number of fuel feeding times is 4 times.

In the case where the number of fuel pumping times during the 360 ° rotation of the cam 22a is performed twice, as shown in FIG. 8A, when the electromagnetic spill valve 54 starts the closing valve, the fuel is pumped from the high pressure fuel pump 47. As a result, the soft pressure P changes from a low value to a high value with respect to the target soft pressure P0, and then the increase in the soft pressure P is stopped when the electromagnetic spill valve 54 is opened. This rise stops and the fixed soft pressure P decreases step by step every time fuel injection is performed, and after two fuel injections, the pressure decreases to the vicinity of the value before the fuel feeding is performed. In this case, it is necessary to discharge the amount of fuel required for one fuel injection in one fuel feed to sufficiently increase the compression pressure P so that the fuel pressure P does not drop excessively by the two fuel injections. Then, the closing valve start timing (close valve timing) of the electromagnetic spill valve 54 is adjusted so as to sufficiently increase the soft pressure P.

In addition, in the case where the number of fuel pressure feeds during the 360 ° rotation of the cam 22a is four times, as shown in FIG. 8B, when the solenoid spill valve 54 starts the closing valve, the fuel is discharged from the high pressure fuel pump 47. The soft pressure P is changed from a low value to a high value with respect to the target soft pressure P0, and then the increase in the soft pressure P is stopped when the electromagnetic spill valve 54 is opened. After the fuel injection has been performed once, the rise in the constant pressure (P) is lowered to the vicinity of the value before the fuel feeding is performed. After that, the value higher than the target pressure (P0) is again increased by the fuel feeding. do. In this case, since only the amount of fuel required for one fuel injection is sent out in one fuel feed, the pressure is increased as the number of times of the fuel feed recovery is performed twice during the 360 ° rotation of the cam 22a as described above. It is not necessary to raise (P). Therefore, when the solenoid spill valve 54 is closed valve | bulb to raise the said soft-pressure P, the same closing valve start time is delayed compared with the case, and a closing valve time becomes short.

By changing the number of fuel feeds during the 360 ° rotation of the cam 22a in this way, even if the fuel injection amount is constant, the amount of one fuel feed required is changed, so the closing valve of the electromagnetic spill valve 54 It is possible to adjust the start time. In this embodiment, the closing valve start timing of the electromagnetic spill valve 54 is obtained by setting the number of times of fuel pressure feeding during the 360 ° rotation of the cam 22a to, for example, four times. Is positioned within a predetermined cam angle range A. As a result, only by changing the closing valve start time of the electromagnetic spill valve 54 within the predetermined cam angle range A, it is possible to perform the same fuel feed amount adjustment to obtain the required fuel feed amount.

In the change of the closing valve start time of the electromagnetic spill valve 54 in this predetermined cam angle range A, the amount of cam speed changes at the start of the closing valve by the same change becomes substantially constant irrespective of the cam phase. Therefore, it becomes difficult to change the amount of change of the fuel feed amount at the time of changing the closing valve start time of the electromagnetic spill valve 54 according to cam phase. Therefore, by changing the closing valve start timing of the electromagnetic spill valve 54, it is possible to easily adjust the exact amount of fuel feeding, and the same pressure P in bringing the pressure P as close to the target pressure P0. ) Can be suppressed from large fluctuations.

According to this embodiment mentioned above, the effect shown below is acquired.

Predetermined cam angle range in which the closing valve start time of the electromagnetic spill valve 54 at the time of obtaining the maximum fuel injection amount required for fuel injection changes the cam speed to the decrease side with a constant slope with respect to the phase change of the cam 22a. The number of fuel pressure feeds of the high pressure fuel pump 47 during the 360 ° rotation of the cam 22a was set to four times so as to be located in (A). By thus setting the fuel feed frequency, the closing valve start timing change of the electromagnetic spill valve 54 for adjusting the fuel feed amount is performed within the predetermined cam angle range A. By changing the closing valve start timing of the electromagnetic spill valve 54, it is possible to easily adjust the precise fuel feeding amount, and the same soft pressure P is obtained when the soft pressure P is brought close to the target soft pressure P0. A large fluctuation can be suppressed.

Next, a third embodiment of the present invention will be described. In the present embodiment, only the method of positioning the closing valve start time of the electromagnetic spill valve 54 in which the maximum required fuel feed amount is obtained within the predetermined cam angle range A is different from that of the first and second embodiments. different. Therefore, only the parts different from the first and second embodiments will be described in this embodiment, and detailed descriptions of the same parts as the first and second embodiments will be omitted.

In the high pressure fuel pump 47, the pressure chamber 49 is provided under the condition that the moving width (stroke) of the plunger 48b with respect to the cylinder 48a and the closing valve start time of the electromagnetic spill valve 54 are made constant. The larger the inner diameter, the greater the amount of fuel feed per stroke. In the present embodiment, the high-pressure fuel pump is positioned so that the closing valve start time of the electromagnetic spill valve 54 at which the maximum amount of the fuel feed amount required is obtained is located near the most advanced angle position in the predetermined cam angle range A. The inner diameter of the pressurizing chamber 49 in 47 is set. The internal diameter setting in the pressurizing chamber 49 is performed by adjusting the diameter of the cylinder 48a and the plunger 48b.

According to this embodiment, the effect shown below is obtained.

Predetermined cam angle range in which the closing valve start time of the electromagnetic spill valve 54 at the time of obtaining the maximum fuel injection amount required for fuel injection changes the cam speed to the decrease side with a constant slope with respect to the phase change of the cam 22a. The inner diameter of the pressurization chamber 49 in the high pressure fuel pump 47 was set so that it might be located in (A). By setting the inner diameter in the pressurizing chamber 49 in this way, the closing valve start timing change of the electromagnetic spill valve 54 for adjusting the fuel feeding amount is performed within the predetermined cam angle range A. By changing the closing valve start timing of the electromagnetic spill valve 54, it is possible to easily adjust the exact amount of fuel feed, so that the same soft pressure P is obtained when the soft pressure P is brought close to the target soft pressure P0. A large fluctuation can be suppressed.

When the closing valve start time of the electromagnetic spill valve 54 when obtaining the maximum value of the fuel feed amount required for fuel injection is located near the most angle position within the predetermined cam angle range A, the electromagnetic spill valve ( The closing valve of 54 ends when the cam 22a is located near the top dead center. Therefore, the closing valve start timing change of the electromagnetic spill valve 54 for adjusting the fuel feeding amount is changed from the vicinity of the nearest angle in the predetermined cam angle range A until the cam 22a is located near the top dead center. It can be performed in a wide range, and the adjustment width of fuel feed amount can be made wide.

In addition, each said Example can also be changed as follows, for example.

In each of the above embodiments, the three types of methods of locating the closing valve start timing of the electromagnetic spill valve 54 in which the maximum required fuel feed amount is obtained within the predetermined cam angle range A are exemplified, but one of them is used. Instead of employing one method independently, two or more methods may be used in combination. In this case, it is possible to position the closing valve start time of the solenoid spill valve 54 in which the maximum value of the required amount of fuel feed amount can be positioned within the predetermined cam angle range A more accurately, thereby accurately adjusting the fuel feed amount adjustment. By doing so, the controllability of the same fuel feeding amount can be improved.

In the second embodiment, the case where the high-pressure fuel pump 47 is driven using the cam 22a on which four canisters 22b are formed is described. However, the number of the cans 22b is not limited to four. 3 or 5 or more may be appropriately changed. For example, if the cam peak 22b is four or more, the number of fuel feeds in a predetermined period can be adjusted in detail, and the setting range of the fuel feeds number during the 360 ° rotation of the cam 22a can be broadly taken. Will be. In this case, during the 360 ° rotation of the cam 22a, provided that the closing valve start timing of the electromagnetic spill valve 54 at which the maximum amount of the fuel feed amount required is obtained is within the predetermined cam angle range A. May be appropriately changed to a value other than four times. In addition, in this case, the closing valve start timing of the electromagnetic spill valve 54 in which the maximum value of the required fuel feeding amount is obtained is positioned near the nearest angle position in the predetermined cam angle range A, and the electromagnetic spill valve ( It is preferable to make it possible to change the closing valve start timing of 54) in a wide range.

In the first embodiment, the cam 22a is positioned near the top dead center in order to position the closing valve start time of the electromagnetic spill valve 54 in which the maximum required fuel feed amount is obtained within the predetermined cam angle range A. The lift amount of the plunger 48b at the time of positioning was set to the cam profile of the cam 22a so that it might become larger than normal. Instead, by setting the cam profile of the cam 22a to a cam profile in which the predetermined cam angle range A becomes larger than usual, the closing valve start timing of the solenoid spill valve 54 at which the maximum value of the required fuel feeding amount is obtained is obtained. May be positioned within the predetermined cam angle range A.

In each of the above embodiments, the closing valve end (opening valve) timing of the electromagnetic spill valve 54 in the pressure feeding stroke of the high-pressure fuel pump 47 was set when the cam 22a was positioned at the top dead center. You may change it.

In each of the above embodiments, the closing valve start timing of the solenoid spill valve 54 in the pressure stroke of the high-pressure fuel pump 47 is positioned near the nearest angle position within the predetermined cam angle range A, but this is appropriately changed. You may also

In each said embodiment, although this invention was applied to the fuel supply apparatus of a gasoline engine, you may apply this invention to the fuel supply apparatus of a diesel engine instead.

Claims (7)

The volume of the pressurizing chamber 49 is changed based on the relative movement between the cylinder 48a and the plunger 48b by the rotation of the cam 22a, and the fuel is sucked into the pressurizing chamber 49 to draw this fuel into the fuel of the internal combustion engine. It is provided with the fuel pump 47 which pumps toward the injection valve 40, the spill passage 50 which discharges fuel from the said pressurization chamber 49, and the spill valve 54 which opens and closes between this pressurization chamber 49. In the fuel supply apparatus of the internal combustion engine which adjusts the fuel feed amount from the said fuel pump 47 to the said fuel injection valve 40 by controlling the closing valve timing of the said spill valve 49, By changing the closing valve start time of the spill valve 54 to control the closing valve period of the spill valve 54, the fuel pump 47 required for fuel injection of the fuel injection valve 40 is removed. And control means 92 for obtaining a fuel feeding amount, The fuel supply device includes the cylinder 48a and the plunger when the closing valve start time of the spill valve 54 when the maximum required fuel feed amount is obtained is rotated by the cam 22a by a unit angle. A fuel supply device for an internal combustion engine, characterized in that the amount of relative movement with the 48b is set within a predetermined cam angle range which is shifted by a predetermined slope with respect to the phase change of the cam 22a. The method of claim 1, The control means 92 terminates the closing valve engine of the spill valve 54 when the cam 22a is near the top dead center, The closing valve start timing of the spill valve 54 at the time of obtaining the maximum required fuel injection amount is set such that the closing valve starting timing is located near the most angular position within the predetermined cam angle range. Fuel supply of an internal combustion engine. The method according to claim 1 or 2, The fuel supply device is constituted by a cam 22a in which a cam profile is set such that the closing valve start timing of the spill valve 54 when the maximum value of the required fuel feeding amount is obtained is within the predetermined cam angle range. A fuel supply device for an internal combustion engine. The method according to claim 1 or 2, The fuel supply apparatus has a cam mount in which the number of fuel pressure feeds at a predetermined cam angle is set such that the closing valve start time of the spill valve 54 when the maximum value of the required fuel pressure feed rate is obtained is within the predetermined cam angle range. A fuel supply device for an internal combustion engine, characterized by comprising a cam (22a) having a (22b). The method according to claim 1 or 2, The fuel supply device is a pressure chamber in which the inner diameter of the pressure chamber 49 is set such that the closing valve start time of the spill valve 54 at the time of obtaining the maximum required fuel feed amount is within the predetermined cam angle range. A fuel supply device for an internal combustion engine, which is configured by providing 49. The volume of the pressurizing chamber 49 is changed based on the relative movement between the cylinder 48a and the plunger 48b by the rotation of the cam 22a, and the fuel is sucked into the pressurizing chamber 49 to draw this fuel into the fuel of the internal combustion engine. It is provided with the fuel pump 47 which pumps toward the injection valve 40, the spill passage 50 which discharges fuel from the said pressurization chamber 49, and the spill valve 54 which opens and closes between this pressurization chamber 49. In the manufacturing method of the fuel supply apparatus of the internal combustion engine which adjusts the fuel feed amount from the said fuel pump 47 to the said fuel injection valve 40 by controlling the closing valve timing of the said spill valve 54, When the cam 22a rotates by a unit angle, the cam moves so that the relative movement amount between the cylinder 48a and the plunger 48b is within a predetermined cam angle range which is shifted by a predetermined slope with respect to the phase change of the cam 22a. Molding 22a, The said fuel supply apparatus is comprised so that the closing valve start time of the said spill valve 54 can obtain the fuel pumping amount from the said fuel pump 47 which is needed for the fuel injection of the said fuel injection valve 40. FIG. The manufacturing method of the fuel supply apparatus of an internal combustion engine. The volume of the pressurizing chamber 49 is changed based on the relative movement between the cylinder 48a and the plunger 48b by the rotation of the cam 22a, and the fuel is sucked into the pressurizing chamber 49 to draw this fuel into the fuel of the internal combustion engine. It is provided with the fuel pump 47 which pumps toward the injection valve 40, the spill passage 50 which discharges fuel from the said pressurization chamber 49, and the spill valve 54 which opens and closes between this pressurization chamber 49. And controlling the closing valve timing of the spill valve 54 to adjust the fuel pumping amount from the fuel pump 47 to the fuel injection valve 40. To By controlling the closing valve period of the spill valve 54, the spill valve 54 of the spill valve 54 so as to obtain the fuel feed amount from the fuel pump 47 required for the fuel injection of the fuel injection valve 40. To control when the closing valve starts, The fuel supply device includes the cylinder 48a and the plunger when the closing valve start time of the spill valve 54 when the maximum required fuel feed amount is obtained is rotated by the cam 22a by a unit angle. A fuel supply method for an internal combustion engine, characterized in that the relative movement amount with (48b) is set to be within a predetermined cam angle range which is shifted by a predetermined slope with respect to the phase change of the cam (22a).